Makes it easier to use because you see which square is currently
hovered:
<img width="314" alt="Screenshot 2024-05-02 at 15 38 20"
src="https://github.com/go-gitea/gitea/assets/115237/3a15dad1-2259-4f28-9fae-5cf6ad3d8798">
I did try a `scoped` style for this, but that did not work for some
reason.
(cherry picked from commit 6f89d5e3a0886d02ead732005f593ae003f78f78)
Ran most of the Less files through the Less compiler and Prettier and
then followed up with a round of manual fixes.
The Less compiler had unfortunately stripped all `//` style comments
that I had to restore (It did preserve `/* */` comments). Other fixes
include duplicate selector removal which were revealed after the
transpilation and which weren't caught by stylelint before but now are.
Fixes: https://github.com/go-gitea/gitea/issues/15565